Seat for side wall sampling tools



June 13, 1950, J, MCCLENTON 2,511,508

SEAT FOR SIDE WALL SAMPLING TOOLS Filed Feb. 14, 1946 J'cHN MCL|NT0N INVENTOR.

Jim rs. cam- By mm.

Patented June 13, 1950 UNITED STATES PATENT OFFICE 4 Claims. (Cl. 255-1.4)

The invention relates to a tool for cutting a seat for sidewall sampling tools in well bores.

In the practice of taking sidewall samples it is usual to lower a sampling tool through the drill stem so that it projects through a window in the drill collar and engages the face of the well bore. When the drill collar is lowered the sampler is caused to pivot and is supposed to force its way into the formation so as to obtain a sample thereof. Such procedure is satisfactory in a great many instances, but very often harder formations are encountered and the sampler fails to penetrate or catchon to the formation and slides therealong so that no sample is obtained.

The present invention contemplates a special tool which can be lowered. in the well through the drill stem and which will project through the window in the drill collar so that when the drill stem is rotated it will cut an annular seat in the sidewall of the well bore. the seat cutting tool have been shown, one where a separate cutting tool is used which can then be removed and the sidewall sampling tool lowered into position so that it engages such seat and in this manner a sample is assured, because the sampler readily catches on to the formation due to the preformed seat; and a second form where a combination cutting tool and sampler to first cut the seat and then take the sample in a single trip into the well bore.

It is therefore one of the objects of the present invention to provide a seat cutting tool for sidewall samplers which can be connected to the sampling tool in lieu of the sampler and run into position to cut a seat by rotating the drill stem.

Another object of the invention is to provide a pivoted sidewall sample seat cutter in .a well bore.

Still another object is to cut a seat for a sidewall sampler so as to insure an uncontaminated sample because the mud cake on the face of the formation is cut away. I

It is also an object to provide a combination seat cutter and sampler member for side wall samples so that a seat may be cut and a sample taken in a single trip into the well.

A still further object of the invention is to provide a seat cutting tool which will be caused to penetrate a formation and cut a seat therein when the drill pipe is lowered and rotated.

Other and further objects of the invention will be readily apparent when the following description is considered in connection with the accompanying drawings wherein:

Two forms of Fig. 1 is a vertical sectional view illustrating the well bore with the seat cutting tool in position;

Fig. 2 is a top plane View looking down on the seat cutter;

Fig. 3 is a side elevation on the line 3--3 of Fig. 2 showing a side View of the seat cutter;

Fig. 4 is a side elevation of the combination seat cutter and sampler;

Fig. 5 is a top elevation of the form of the sampler of Fig. 4, and showing the forward seat cutting edge thereon;

Fig. 6 is an end view of the combination seat cutter and sampler of Fig. 5.

In Fig. l the formation 2 has been penetrated by drilling the well bore therethrough. This bore has also penetrated a formation 3 and has in this manner formed the well bore 5. This bore has been formed by rotation of the bit 5 which has the drill collar :5 connected thereto. The drill stem 7 is connected to the upper end of the drill collar and in this manner the drill bit and collar are lowered, raised and rotated in the well bore.

The drill collar 5 has a side opening or window 9 through which the sidewall sampling tool ll] is adapted to project. The sidewall sampler tool is arranged to be lowered into the well bore and will pass into the guide sleeve i2 which is pinned at It to the drill collar. The tool i0 is arranged to be oriented in the sleeve i2 by Virtue of the guideways it which receive the guide ribs [5.

In order to deflect the sampler tool from the drill collar and against the formation 3, a spring mounted deflector plate ll has been illustrated in Fig. 1. In order to hold the sampler assembly in against upward movement in the drill collar while the seat cutting operation is being performed, a hold-down collar is is locked in position in the drill collar by the set screw 2%. Suitable latches on the tool It! will engage in the recesses i8 so as to hold the sampling tool against upward movement.

The tool it as it has been used heretofore is normally provided with. a hollow sampler to be forced into the formation to acquire a sample of such formation. Such sampler is usually a rigid tubular member such as shown in my prior Patent Number 2,176,375 issued October 1'7, 1939.

When a hard formation is encountered, however, the usual sampler may not dig into the formation and no sample would be obtained.

The present invention contemplates a seat cutting instrument to be attached to the tool [0 in lieu of the sampler.

When a seat is to be cut the tool I is run into the well through the drill pipe and has the seat cutting tool 30 connected thereto. This seat cutter 30 is best seen in Figs. 2 and 3, and is made up of a body 3| having an car 32 and an opening 33 so as to pivot the seat cutter on the tool l0 as at the pivot 29 and opening respectively of the sampler.

The end of the seat cutting tool 30 has a cutting portion 34 thereon which is formed by the curved front face 35 so as to provide the end cutting edge 36 and the side cutting edge 37.

In operation if the seat is to be cut, the cutter 39 is connected and the entire tool is then lowered or dropped down through the drill stem I so that the cutter 36 will move out through the window 9 as seen in Fig. 1 and engage the formation so that the corner 49 of the tool will cut into the face 41 of the formation 3. As the load is applied to the cutter 39 by lowering down on the drill stem 1', the cutter is forced into the formation so that the bottom edge 36 and side edge 31 serve to cut the seat 45 upon rotation of the drill stem and the drill collar.

If desired the sampler or seat cutting tool l0 may be retrieved by an overshot 42 arranged to engage the spear head 43 on the top of the tool 10 The overshot 42 may have suitable weights or .jars thereon which can be manipulated to jar the seat cutting tool against the formation.

After the seat cutting tool is retrieved, either another tool may be inserted into the drill pipe which carries a usual type of sampler, or the seat cutter portion 30 of the tool may be replaced with a sample taker. Now while the drill stem is held at the same elevation at which the seat was cut, the tool 40 is lowered into the drill stem. It seems obvious that the outer end of the sampler will move out through the window 9 and will engage the seat 45. Lowering of the drill stem will now cause a sample of such formation to enter the sample chamber in the sampler. There will of course be no rotation of the drill collar in this position. When the seat cutter is used to cut away the formation it also serves to cut or scrape away any mud cake or filter cake which may have formed on the face of the formation 3 so that a clean or more truly representative sample is obtained.

Figs. 4 and and 6 show a modified form 25 of the usual type of sampler wherein the body 26 thereof has been formed with an enlarged or fiat forward face 56 which forms the seat cutting fingers 23 to cut the seat 45. The body 26 is formed with the sample receiving chamber 26'. With this combination seat cutter and sampler '25 in place by passing the pivot pin 29 through the opening 28 in the ear 21, the operation of cutting the seat will be the same as previously described, but then instead of retrieving the tool to the surface the rotation will be stopped and the drill stem moved downwardly or the jars operated to spud the sampler into the seat 45. With such a combination tool the seat may be cut and the sample taken in a single operation. The usual sampler has not been shown but is identical with the tube 25 except that the forward end is circular and slightly tapered.

Broadly the invention contemplates a seat cutter for sidewall samplers so that the seating of the sampler is insured and the formation cleaned of mud cake.

What is claimed is:

1. In a side wall sampling tool assembly including a drill stem, drill collar and drill bit, a side door opening in said drill collar for the sampling tool, and a seat cutting member adapted to be projected through said opening to engage the wall of the well bore, means to latch said cutting member to said collar in projecting position so that rotation of the drill collar with said member projecting therefrom will cut a sampling tool seat in the well wall, said member being removable with a wire line through the drill stem and replaceable with the sampling tool to contact the seat thus cut.

2. A method of obtaining side wall samples from well wall formations into which a side wall sampling tool will not normally penetrate which comprises lowering a seat cutting tool through the drillstem, projecting such tool against the formation to be sampled, rotating the drill stem and projecting tool, forcing the tool against the formation to out a sampling tool seat, replacing the seat cutting tool with a sampling tool, engaging the sampling tool upon the seat out, forcing the sampling tool into the seat to sample the formation, and retrieving the sample tool and sample.

3. A method of obtaining side wall samples from well wall formations into which a side wall sampling tool will not normally penetrate which comprises lowering a seat cutting tool through the drill stem, projecting such tool against the formation .to be sampled, rotating the drill stem and projecting tool, forcing the tool against the formation to out a sampling tool seat, replacing the seat cutting tool with a sampling tool, engaging the sampling tool upon the seat cut, forcing the sampling tool into the seat to sample the formation, and retrieving the sample tool and sample while the drill stem remains in the well bore.

4. A method of obtaining sidewall samples from well wall formations into which a sampling tool will not normally penetrate which comprises lowering a combination sampler and seat cutting member through the drill stem, projecting such member against the formation to be sampled, ro tating the drill stem while advancing the member against the formation face to cut away any filter cake thereon and cut an annular inclined seat, ceasing rotation, and forcing the member into the seat thus formed to sample the formation, and retrieving the tool to the surface.

JOHN MCCLINTON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 281,922 Randall July 24, 1833 2,173,531 De Long l Sept. 19, 1939 2,176,375 McClinton Oct. 17, 1939 2,285,024 Ferguson June 2, 1942 2,344,598 Church Mar. 21, 1944 2,347,726 Auld et al. May 2, 1944 2,358,470 Oswald Sept. 19, 1944 FOREIGN PATENTS Number Country Date 2,355 Great Britain A. D. 1869 

